The use of marks on contact lenses for indicating whether the lens is for the right or left eye is well known. Additionally, it is known to use marks for indicating serial numbers, lot and batch numbers, and optical powers. Finally, marks have been used to measure the rotation of the lens on the eye as well as to orient the lens for inspection by quality control personnel.
One problem with some of the known marks is that they are difficult to see. Thus, a need remains for marks with improved on-eye visibility so that the mark may be used as a diagnostic tool. Additionally, a need remains for marks with improved off-eye visibility so that the wearer may differentiate the inside from the outside of the lens.